Ultra bright points of light randomly appearing
They seem to be very bright specular highlights on the waves :

The fact that &quot;Point.001&quot; has a power of 3MW (!) is of course in cause ; but I guess you won't get the same dramatic effect if you lower that value.
What you can do is render the waves and the lightning in two distinct View Layers (formerly &quot;Render Layers&quot;), apply the fog glow only to the lightning layer, then merge the two layers with a Mix or AlphaOver node.